The investigators will treat 50-100 patients per year for two years; all will be undergoing surgery for hip fracture or hip reconstruction. After preliminary studies and informed consent are obtained, the patients will be randomized into two groups, and treatment begun within six hours after assignment. The treatment group will receive 5000 units of heparin subcutaneously every 12 hours and sulfinpyrazone 200 mg four times a day by mouth. The control group will receive appropriate placebos. Patients with infection, bleeding disorders, recnet trama, iodine toxicity, etc., will be excluded from the study. Laboratory studies will include prothrombin time, partial thromboplastin time (PPT), bleeding time, platelet count, ECG, and chest x-ray (platelet coagulant studies by Dr. Walsh). Data will be recorded. Criteria of effectiveness of the therapy will be based on results of the 125 I labelled fibrinogen assay which will be confirmed by venograph when it is "positive".